The income of a broker remains unchanged though the rate of commission

Question

The income of a broker remains unchanged though the rate of commission is increased from 4% to 5%. The percentage of slump in business is:

A. 8%

B. 1%

C. 20%

d. 80%

E. 5%

niks18 · Answer

Let  S_1  be initial sales and  S_2  be sales after increase in commission %. We need to find  \frac{S_1-S_2}{S_1}

Given  S_1*4 % =S_2*5 %  => \frac{S_2}{S_1}=\frac{4}{5} . subtract both sides of the equation from  1  to get

Or,  1-\frac{S_2}{S_1}=1-\frac{4}{5}

\frac{S_1-S_2}{S_1}=\frac{1}{5} => 20 %

Option  C

raki99 · Answer

Here,
let be the value of business 100
and, the percentage of slump of business is x
So, according to question,
100 * 4/100 = (100-x) * 5/100
4 = (100-x)/20
80 = 100 -x
100 -x = 80
- x = 80-100
-x = -20
x= 20

Bunuel · Answer

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The income of a broker remains unchanged though the rate of commission

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